function genTodayStr() {
    var date = new Date();
    return date.getFullYear() + "-" + formatZero(date.getMonth() + 1) + "-" + formatZero(date.getDate());
}

function genLastYearStr() {
    var date = new Date();
    date.setFullYear(date.getFullYear() - 1);
    return date.getFullYear() + "-" + formatZero(date.getMonth() + 1) + "-" + formatZero(date.getDate());
}

function genLastMonthDayStr() {
    var date = new Date();
    return date.getFullYear() + "-" + formatZero(date.getMonth()) + "-" + formatZero(date.getDate());
}

function genLastWeekDayStr() {
    var date = new Date();
    date.setDate(date.getDate() - 6);
    return date.getFullYear() + "-" + formatZero(date.getMonth() + 1) + "-" + formatZero(date.getDate());
}

function formatZero(n) {
    if (n < 10) {
        return "0" + n;
    } else {
        return n;
    }
}